Method and apparatus for tunable antenna and ground plane for handset applications

ABSTRACT

An embodiment is directed to a device comprising an antenna, a chassis configured to be electrically coupled to the antenna and comprising a slot loaded with at least one tunable component, wherein: the slot is aligned along a longitudinal edge of the chassis, the slot is formed in an area of the chassis based on an identification of currents in the area, and the antenna and chassis are electrically connected at a location based on the area.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.13/647,959 filed Oct. 9, 2012 by Ali et al., entitled “Method andApparatus for Tunable Antenna and Ground Plane for HandsetApplications.” All sections of the aforementioned applications areincorporated herein by reference in its entirety.

BACKGROUND

Advancements in computing technologies have made it possible to expandthe scope and extent of communications capabilities. For example, mobileor handheld devices are in use for purposes of communication. Suchdevices may be used to, e.g., engage in a phone call or transmit orreceive data.

Recent trends have dictated that devices be made as small as possible.For example, combining the small size of a mobile device with theincreasing use of mobile devices presents a number of challenges.Antennas and filters associated with a mobile device must be able todiscriminate between a number of signals to obtain a particular signalof interest. An antenna also needs to be an efficient radiator. However,all other things being equal, if a device is manufactured in accordancewith a smaller form factor, performance might be compromised when usinga correspondingly smaller antenna. Improvements in antenna design andmanufacture are needed to accommodate smaller devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be understood, and its numerous objects,features and advantages obtained, when the following detaileddescription is considered in conjunction with the following drawings, inwhich:

FIG. 1 depicts an exemplary system in which the present disclosure maybe implemented;

FIG. 2 shows a wireless-enabled communications environment including anembodiment of a client node;

FIG. 3 is a simplified block diagram of an exemplary client nodecomprising a digital signal processor (DSP);

FIG. 4 is an exemplary schematic in accordance with one or moreembodiments;

FIG. 5 is an exemplary chassis in accordance with one or moreembodiments;

FIG. 6A is an exemplary chassis in accordance with one or moreembodiments;

FIG. 6B is an exemplary chassis in accordance with one or moreembodiments;

FIG. 7 is a flow chart of an exemplary method in accordance with one ormore embodiments;

FIG. 8 is an exemplary antenna in accordance with one or moreembodiments;

FIG. 9 is an exemplary antenna in accordance with one or moreembodiments;

FIG. 10 is an exemplary antenna in accordance with one or moreembodiments;

FIG. 11 is an exemplary antenna in accordance with one or moreembodiments;

FIG. 12A is a flow chart of an exemplary method in accordance with oneor more embodiments;

FIG. 12B is a flow chart of an exemplary method in accordance with oneor more embodiments;

FIG. 13A is a line drawing of an exemplary chassis coupled to an antennain accordance with one or more embodiments;

FIG. 13B is a zoomed-in, perspective view of the antenna of FIG. 13B;

FIG. 14 is a line drawing of an exemplary antenna in accordance with oneor more embodiments;

FIG. 15 is a line drawing of an exemplary antenna in accordance with oneor more embodiments; and

FIG. 16 is a line drawing of an exemplary antenna in accordance with oneor more embodiments.

DETAILED DESCRIPTION

The present disclosure is directed in general to communications systemsand methods for operating same. In one aspect, the present disclosurerelates to controlling radiation associated with an antenna. In someembodiments, the radiation may be controlled based on a modification ofa ground plane, or a chassis associated with the ground plane. In someembodiments, the radiation may be controlled via a modification of astructure of the antenna.

An embodiment is directed to a device comprising an antenna, a chassisconfigured to be electrically coupled to the antenna and comprising aslot loaded with at least one tunable component, wherein: the slot isaligned along a longitudinal edge of the chassis, the slot is formed inan area of the chassis based on an identification of currents in thearea, and the antenna and chassis are electrically connected at alocation based on the area.

An embodiment is directed to a device comprising a chassis, an antennaconfigured to be electrically coupled to the chassis based on analignment of an elongated part of a structure of the antenna with alongitudinal edge of the chassis, and at least one tunable componentthat is loaded at a location on the antenna structure, where thelocation is based on an identification of a maximum surface current at aparticular operating frequency.

An embodiment is directed to a method for controlling radiationassociated with an antenna via a modification of a ground plane,comprising identifying currents in an area of a chassis electricallycoupled to the antenna to select a location to electrically connect theantenna and chassis, forming a slot in the area to confine and controlthe currents, aligning the formed slot to a longitudinal edge of thechassis loading the slot with at least one tunable component, tuning theslot to obtain a specified radiation performance of the antenna, andtuning the slot to control a current on the antenna surface to obtain afrequency tuning through the electrical coupling to the chassis.

An embodiment is directed to a method for controlling radiationassociated with an antenna via a modification of a structure of theantenna, comprising selecting a location on the radiating structure witha maximum surface current at a frequency of interest to place at leastone tunable element, loading the at least one tunable element at thelocation, and electrically coupling the antenna to a chassis by aligningan elongated part of the structure with a longitudinal edge of thechassis.

Various illustrative embodiments of the present disclosure will now bedescribed in detail with reference to the accompanying figures. Whilevarious details are set forth in the following description, it will beappreciated that the present disclosure may be practiced without thesespecific details, and that numerous implementation-specific decisionsmay be made to the disclosure described herein to achieve specificgoals, such as compliance with process technology or design-relatedconstraints, which will vary from one implementation to another. Whilesuch a development effort might be complex and time-consuming, it wouldnevertheless be a routine undertaking for those of skill in the arthaving the benefit of this disclosure. For example, selected aspects areshown in block diagram and flowchart form, rather than in detail, inorder to avoid limiting or obscuring the present disclosure. Inaddition, some portions of the detailed descriptions provided herein arepresented in terms of algorithms or operations on data within a computermemory. Such descriptions and representations are used by those skilledin the art to describe and convey the substance of their work to othersskilled in the art.

As used herein, the terms “component,” “system” and the like areintended to refer to a computer-related entity, either hardware,software, a combination of hardware and software, or software inexecution. For example, a component may be, but is not limited to being,a processor, a process running on a processor, an object, an executableinstruction sequence, a thread of execution, a program, or a computer.By way of illustration, both an application running on a computer andthe computer itself can be a component. One or more components mayreside within a process or thread of execution and a component may belocalized on one computer or distributed between two or more computers.

As likewise used herein, the term “node” broadly refers to a connectionpoint, such as a redistribution point or a communication endpoint, of acommunication environment, such as a network. Accordingly, such nodesrefer to an active electronic device capable of sending, receiving, orforwarding information over a communications channel. Examples of suchnodes include data circuit-terminating equipment (DCE), such as a modem,hub, bridge or switch, and data terminal equipment (DTE), such as ahandset, a printer or a host computer (e.g., a router, workstation orserver). Examples of local area network (LAN) or wide area network (WAN)nodes include computers, packet switches, cable modems, Data SubscriberLine (DSL) modems, and wireless LAN (WLAN) access points. Examples ofInternet or Intranet nodes include host computers identified by anInternet Protocol (IP) address, bridges and WLAN access points.Likewise, examples of nodes in cellular communication include basestations, relays, base station controllers, radio network controllers,home location registers (HLR), visited location registers (VLR), GatewayGPRS Support Nodes (GGSN), Serving GPRS Support Nodes (SGSN), ServingGateways (S-GW), and Packet Data Network Gateways (PDN-GW).

Other examples of nodes include client nodes, server nodes, peer nodesand access nodes. As used herein, a client node may refer to wirelessdevices such as mobile telephones, smart phones, personal digitalassistants (PDAs), handheld devices, portable computers, tabletcomputers, and similar devices or other user equipment (UE) that hastelecommunications capabilities. Such client nodes may likewise refer toa mobile, wireless device, or alternatively, to devices that havesimilar capabilities that are not generally transportable, such asdesktop computers, set-top boxes, or sensors. A network node, as usedherein, generally includes all nodes with the exception of client nodes,server nodes and access nodes. Likewise, a server node, as used herein,refers to an information processing device (e.g., a host computer), orseries of information processing devices, that perform informationprocessing requests submitted by other nodes. As likewise used herein, apeer node may sometimes serve as client node, and at other times, aserver node. In a peer-to-peer or overlay network, a node that activelyroutes data for other networked devices as well as itself may bereferred to as a supernode.

An access node, as used herein, refers to a node that provides a clientnode access to a communication environment. Examples of access nodesinclude cellular network base stations and wireless broadband (e.g.,WiFi, WiMAX, etc.) access points, which provide corresponding cell andWLAN coverage areas. As used herein, a macrocell is used to generallydescribe a traditional cellular network cell coverage area. Suchmacrocells are typically found in rural areas, along highways, or inless populated areas. As likewise used herein, a microcell refers to acellular network cell with a smaller coverage area than that of amacrocell. Such micro cells are typically used in a densely populatedurban area. Likewise, as used herein, a picocell refers to a cellularnetwork coverage area that is less than that of a microcell. An exampleof the coverage area of a picocell may be a large office, a shoppingmall, or a train station. A femtocell, as used herein, currently refersto the smallest commonly accepted area of cellular network coverage. Asan example, the coverage area of a femtocell is sufficient for homes orsmall offices.

In general, a coverage area of less than two kilometers typicallycorresponds to a microcell, 200 meters or less for a picocell, and onthe order of 10 meters for a femtocell. The actual dimensions of thecell may depend on the radio frequency of operation, the radiopropagation conditions and the density of communications traffic. Aslikewise used herein, a client node communicating with an access nodeassociated with a macrocell is referred to as a “macrocell client.”Likewise, a client node communicating with an access node associatedwith a microcell, picocell, or femtocell is respectively referred to asa “microcell client,” “picocell client,” or “femtocell client.”

The term “article of manufacture” (or alternatively, “computer programproduct”) as used herein is intended to encompass a computer programaccessible from any computer-readable device or media. For example,computer readable media can include but are not limited to magneticstorage devices (e.g., hard disk, floppy disk, magnetic strips, etc.),optical disks such as a compact disk (CD) or digital versatile disk(DVD), smart cards, and flash memory devices (e.g., card, stick, etc.).

The word “exemplary” is used herein to mean serving as an example,instance, or illustration. Any aspect or design described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other aspects or designs. Those of skill in the artwill recognize many modifications may be made to this configurationwithout departing from the scope, spirit or intent of the claimedsubject matter. Furthermore, the disclosed subject matter may beimplemented as a system, method, apparatus, or article of manufactureusing standard programming and engineering techniques to producesoftware, firmware, hardware, or any combination thereof to control acomputer or processor-based device to implement aspects detailed herein.

FIG. 1 illustrates an example of a system 100 suitable for implementingone or more embodiments disclosed herein. In various embodiments, thesystem 100 comprises a processor 110, which may be referred to as acentral processor unit (CPU) or digital signal processor (DSP), networkconnectivity interfaces 120, random access memory (RAM) 130, read onlymemory (ROM) 140, secondary storage 150, and input/output (I/O) devices160. In some embodiments, some of these components may not be present ormay be combined in various combinations with one another or with othercomponents not shown. These components may be located in a singlephysical entity or in more than one physical entity. Any actionsdescribed herein as being taken by the processor 110 might be taken bythe processor 110 alone or by the processor 110 in conjunction with oneor more components shown or not shown in FIG. 1.

The processor 110 executes instructions, codes, computer programs, orscripts that it might access from the network connectivity interfaces120, RAM 130, or ROM 140. While only one processor 110 is shown,multiple processors may be present. Thus, while instructions may bediscussed as being executed by a processor 110, the instructions may beexecuted simultaneously, serially, or otherwise by one or multipleprocessors 110 implemented as one or more CPU chips.

In various embodiments, the network connectivity interfaces 120 may takethe form of modems, modem banks, Ethernet devices, universal serial bus(USB) interface devices, serial interfaces, token ring devices, fiberdistributed data interface (FDDI) devices, wireless local area network(WLAN) devices (including radio, optical or infra-red signals), radiotransceiver devices such as code division multiple access (CDMA)devices, global system for mobile communications (GSM) radio transceiverdevices, long term evolution (LTE) radio transceiver devices, worldwideinteroperability for microwave access (WiMAX) devices, and/or otherwell-known interfaces for connecting to networks, including PersonalArea Networks (PANs) such as Bluetooth. These network connectivityinterfaces 120 may enable the processor 110 to communicate with theInternet or one or more telecommunications networks or other networksfrom which the processor 110 might receive information or to which theprocessor 110 might output information.

The network connectivity interfaces 120 may also be capable oftransmitting or receiving data wirelessly in the form of electromagneticwaves, such as radio frequency signals or microwave frequency signals.Information transmitted or received by the network connectivityinterfaces 120 may include data that has been processed by the processor110 or instructions that are to be executed by processor 110. The datamay be ordered according to different sequences as may be desirable foreither processing or generating the data or transmitting or receivingthe data.

In various embodiments, the RAM 130 may be used to store volatile dataand instructions that are executed by the processor 110. The ROM 140shown in FIG. 1 may likewise be used to store instructions and data thatis read during execution of the instructions. The secondary storage 150is typically comprised of one or more disk drives, solid state drives,or tape drives and may be used for non-volatile storage of data or as anoverflow data storage device if RAM 130 is not large enough to hold allworking data. Secondary storage 150 may likewise be used to storeprograms that are loaded into RAM 130 when such programs are selectedfor execution. The I/O devices 160 may include liquid crystal displays(LCDs), Light Emitting Diode (LED) displays, Organic Light EmittingDiode (OLED) displays, projectors, televisions, touch screen displays,keyboards, keypads, switches, dials, mice, track balls, track pads,voice recognizers, card readers, paper tape readers, printers, videomonitors, or other well-known input/output devices.

FIG. 2 shows a wireless-enabled communications environment including anembodiment of a client node as implemented in an embodiment of thedisclosure. Though illustrated as a mobile phone, the client node 202may take various forms including a wireless handset, a pager, a smartphone, or a personal digital assistant (PDA). In various embodiments,the client node 202 may also comprise a portable computer, a tabletcomputer, a laptop computer, or any computing device operable to performdata communication operations. Many suitable devices combine some or allof these functions. In some embodiments, the client node 202 is not ageneral purpose computing device like a portable, laptop, or tabletcomputer, but rather is a special-purpose communications device such asa telecommunications device installed in a vehicle. The client node 202may likewise be a device, include a device, or be included in a devicethat has similar capabilities but that is not transportable, such as adesktop computer, a set-top box, or a network node. In these and otherembodiments, the client node 202 may support specialized activities suchas gaming, inventory control, job control, task management functions,and so forth.

In various embodiments, the client node 202 includes a display 204. Inthese and other embodiments, the client node 202 may likewise include atouch-sensitive surface, a keyboard or other input keys 206 generallyused for input by a user. The input keys 206 may likewise be a full orreduced alphanumeric keyboard such as QWERTY, DVORAK, AZERTY, andsequential keyboard types, or a traditional numeric keypad with alphabetletters associated with a telephone keypad. The input keys 206 maylikewise include a trackwheel, an exit or escape key, a trackball, andother navigational or functional keys, which may be moved to differentpositions, e.g., inwardly depressed, to provide further input function.The client node 202 may likewise present options for the user to select,controls for the user to actuate, and cursors or other indicators forthe user to direct.

The client node 202 may further accept data entry from the user,including numbers to dial or various parameter values for configuringthe operation of the client node 202. The client node 202 may furtherexecute one or more software or firmware applications in response touser commands These applications may configure the client node 202 toperform various customized functions in response to user interaction.Additionally, the client node 202 may be programmed or configuredover-the-air (OTA), for example from a wireless network access node ‘A’210 through ‘n’ 216 (e.g., a base station), a server node 224 (e.g., ahost computer), or a peer client node 202.

Among the various applications executable by the client node 202 are aweb browser, which enables the display 204 to display a web page. Theweb page may be obtained from a server node 224 through a wirelessconnection with a wireless network 220. As used herein, a wirelessnetwork 220 broadly refers to any network using at least one wirelessconnection between two of its nodes. The various applications maylikewise be obtained from a peer client node 202 or other system over aconnection to the wireless network 220 or any other wirelessly-enabledcommunication network or system.

In various embodiments, the wireless network 220 comprises a pluralityof wireless sub-networks (e.g., cells with corresponding coverage areas)‘A’ 212 through ‘n’ 218. As used herein, the wireless sub-networks ‘A’212 through ‘n’ 218 may variously comprise a mobile wireless accessnetwork or a fixed wireless access network. In these and otherembodiments, the client node 202 transmits and receives communicationsignals, which are respectively communicated to and from the wirelessnetwork nodes ‘A’ 210 through ‘n’ 216 by wireless network antennas ‘A’208 through ‘n’ 214 (e.g., cell towers). In turn, the communicationsignals are used by the wireless network access nodes ‘A’ 210 through‘n’ 216 to establish a wireless communication session with the clientnode 202. As used herein, the network access nodes ‘A’ 210 through ‘n’216 broadly refer to any access node of a wireless network. As shown inFIG. 2, the wireless network access nodes ‘A’ 210 through ‘n’ 216 arerespectively coupled to wireless sub-networks ‘A’ 212 through ‘n’ 218,which are in turn connected to the wireless network 220.

In various embodiments, the wireless network 220 is coupled to a corenetwork 222, e.g., a global computer network such as the Internet. Viathe wireless network 220 and the core network 222, the client node 202has access to information on various hosts, such as the server node 224.In these and other embodiments, the server node 224 may provide contentthat may be shown on the display 204 or used by the client nodeprocessor 110 for its operations. Alternatively, the client node 202 mayaccess the wireless network 220 through a peer client node 202 acting asan intermediary, in a relay type or hop type of connection. As anotheralternative, the client node 202 may be tethered and obtain its datafrom a linked device that is connected to the wireless sub-network 212.Skilled practitioners of the art will recognize that many suchembodiments are possible and the foregoing is not intended to limit thespirit, scope, or intention of the disclosure.

FIG. 3 depicts a block diagram of an exemplary client node asimplemented with a digital signal processor (DSP) in accordance with anembodiment of the disclosure. While various components of a client node202 are depicted, various embodiments of the client node 202 may includea subset of the listed components or additional components not listed.As shown in FIG. 3, the client node 202 includes a DSP 302 and a memory304. As shown, the client node 202 may further include an antenna andfront end unit 306, a radio frequency (RF) transceiver 308, an analogbaseband processing unit 310, a microphone 312, an earpiece speaker 314,a headset port 316, a bus 318, such as a system bus or an input/output(I/O) interface bus, a removable memory card 320, a universal serial bus(USB) port 322, a short range wireless communication sub-system 324, analert 326, a keypad 328, a liquid crystal display (LCD) 330, which mayinclude a touch sensitive surface, an LCD controller 332, acharge-coupled device (CCD) camera 334, a camera controller 336, and aglobal positioning system (GPS) sensor 338, and a power managementmodule 340 operably coupled to a power storage unit, such as a battery342. In various embodiments, the client node 202 may include anotherkind of display that does not provide a touch sensitive screen. In oneembodiment, the DSP 302 communicates directly with the memory 304without passing through the input/output interface (“Bus”) 318.

In various embodiments, the DSP 302 or some other form of controller orcentral processing unit (CPU) operates to control the various componentsof the client node 202 in accordance with embedded software or firmwarestored in memory 304 or stored in memory contained within the DSP 302itself. In addition to the embedded software or firmware, the DSP 302may execute other applications stored in the memory 304 or madeavailable via information media such as portable data storage media likethe removable memory card 320 or via wired or wireless networkcommunications. The application software may comprise a compiled set ofmachine-readable instructions that configure the DSP 302 to provide thedesired functionality, or the application software may be high-levelsoftware instructions to be processed by an interpreter or compiler toindirectly configure the DSP 302.

The antenna and front end unit 306 may be provided to convert betweenwireless signals and electrical signals, enabling the client node 202 tosend and receive information from a cellular network or some otheravailable wireless communications network or from a peer client node202. In an embodiment, the antenna and front end unit 106 may includemultiple antennas to support beam forming and/or multiple input multipleoutput (MIMO) operations. As is known to those skilled in the art, MIMOoperations may provide spatial diversity, which can be used to overcomedifficult channel conditions or to increase channel throughput.Likewise, the antenna and front-end unit 306 may include antenna tuningor impedance matching components, RF power amplifiers, or low noiseamplifiers.

In various embodiments, the RF transceiver 308 provides frequencyshifting, converting received RF signals to baseband and convertingbaseband transmit signals to RF. In some descriptions a radiotransceiver or RF transceiver may be understood to include other signalprocessing functionality such as modulation/demodulation,coding/decoding, interleaving/deinterleaving, spreading/despreading,inverse fast Fourier transforming (IFFT)/fast Fourier transforming(FFT), cyclic prefix appending/removal, and other signal processingfunctions. For the purposes of clarity, the description here separatesthe description of this signal processing from the RF and/or radio stageand conceptually allocates that signal processing to the analog basebandprocessing unit 310 or the DSP 302 or other central processing unit. Insome embodiments, the RF Transceiver 108, portions of the Antenna andFront End 306, and the analog base band processing unit 310 may becombined in one or more processing units and/or application specificintegrated circuits (ASICs).

Note that in this diagram the radio access technology (RAT) RAT1 andRAT2 transceivers 354, 358, the IXRF 356, the IRSL 352 and Multi-RATsubsystem 350 are operably coupled to the RF transceiver 308 and analogbaseband processing unit 310 and then also coupled to the antenna andfront end 306 via the RF transceiver 308. As there may be multiple RATtransceivers, there will typically be multiple antennas or front ends306 or RF transceivers 308, one for each RAT or band of operation.

The analog baseband processing unit 310 may provide various analogprocessing of inputs and outputs for the RF transceivers 308 and thespeech interfaces (312, 314, 316). For example, the analog basebandprocessing unit 310 receives inputs from the microphone 312 and theheadset 316 and provides outputs to the earpiece 314 and the headset316. To that end, the analog baseband processing unit 310 may have portsfor connecting to the built-in microphone 312 and the earpiece speaker314 that enable the client node 202 to be used as a cell phone. Theanalog baseband processing unit 310 may further include a port forconnecting to a headset or other hands-free microphone and speakerconfiguration. The analog baseband processing unit 310 may providedigital-to-analog conversion in one signal direction andanalog-to-digital conversion in the opposing signal direction. Invarious embodiments, at least some of the functionality of the analogbaseband processing unit 310 may be provided by digital processingcomponents, for example by the DSP 302 or by other central processingunits.

The DSP 302 may perform modulation/demodulation, coding/decoding,interleaving/deinterleaving, spreading/despreading, inverse fast Fouriertransforming (IFFT)/fast Fourier transforming (FFT), cyclic prefixappending/removal, and other signal processing functions associated withwireless communications. In an embodiment, for example in a codedivision multiple access (CDMA) technology application, for atransmitter function the DSP 302 may perform modulation, coding,interleaving, and spreading, and for a receiver function the DSP 302 mayperform despreading, deinterleaving, decoding, and demodulation. Inanother embodiment, for example in an orthogonal frequency divisionmultiplex access (OFDMA) technology application, for the transmitterfunction the DSP 302 may perform modulation, coding, interleaving,inverse fast Fourier transforming, and cyclic prefix appending, and fora receiver function the DSP 302 may perform cyclic prefix removal, fastFourier transforming, deinterleaving, decoding, and demodulation. Inother wireless technology applications, yet other signal processingfunctions and combinations of signal processing functions may beperformed by the DSP 302.

The DSP 302 may communicate with a wireless network via the analogbaseband processing unit 310. In some embodiments, the communication mayprovide Internet connectivity, enabling a user to gain access to contenton the Internet and to send and receive e-mail or text messages. Theinput/output interface 318 interconnects the DSP 302 and variousmemories and interfaces. The memory 304 and the removable memory card320 may provide software and data to configure the operation of the DSP302. Among the interfaces may be the USB interface 322 and the shortrange wireless communication sub-system 324. The USB interface 322 maybe used to charge the client node 202 and may also enable the clientnode 202 to function as a peripheral device to exchange information witha personal computer or other computer system. The short range wirelesscommunication sub-system 324 may include an infrared port, a Bluetoothinterface, an IEEE 802.11 compliant wireless interface, or any othershort range wireless communication sub-system, which may enable theclient node 202 to communicate wirelessly with other nearby client nodesand access nodes. The short-range wireless communication Sub-system 324may also include suitable RF Transceiver, Antenna and Front Endsubsystems.

The input/output interface (“Bus”) 318 may further connect the DSP 302to the alert 326 that, when triggered, causes the client node 202 toprovide a notice to the user, for example, by ringing, playing a melody,or vibrating. The alert 326 may serve as a mechanism for alerting theuser to any of various events such as an incoming call, a new textmessage, and an appointment reminder by silently vibrating, or byplaying a specific pre-assigned melody for a particular caller.

The keypad 328 couples to the DSP 302 via the I/O interface (“Bus”) 318to provide one mechanism for the user to make selections, enterinformation, and otherwise provide input to the client node 202. Thekeyboard 328 may be a full or reduced alphanumeric keyboard such asQWERTY, DVORAK, AZERTY and sequential types, or a traditional numerickeypad with alphabet letters associated with a telephone keypad. Theinput keys may likewise include a trackwheel, track pad, an exit orescape key, a trackball, and other navigational or functional keys,which may be inwardly depressed to provide further input function.Another input mechanism may be the LCD 330, which may include touchscreen capability and also display text and/or graphics to the user. TheLCD controller 332 couples the DSP 302 to the LCD 330.

The CCD camera 334, if equipped, enables the client node 202 to makedigital pictures. The DSP 302 communicates with the CCD camera 334 viathe camera controller 336. In another embodiment, a camera operatingaccording to a technology other than Charge Coupled Device cameras maybe employed. The GPS sensor 338 is coupled to the DSP 302 to decodeglobal positioning system signals or other navigational signals, therebyenabling the client node 202 to determine its position. The GPS sensor338 may be coupled to an antenna and front end (not shown) suitable forits band of operation. Various other peripherals may also be included toprovide additional functions, such as radio and television reception.

In various embodiments, the client node (e.g., 202) comprises a firstRadio Access Technology (RAT) transceiver 354 and a second RATtransceiver 358. As shown in FIG. 3, and described in greater detailherein, the RAT transceivers ‘1’ 354 and ‘2’ 358 are in turn coupled toa multi-RAT communications subsystem 350 by an Inter-RAT SupervisoryLayer Module 352. In turn, the multi-RAT communications subsystem 350 isoperably coupled to the Bus 318. Optionally, the respective radioprotocol layers of the first Radio Access Technology (RAT) transceiver354 and the second RAT transceiver 358 are operably coupled to oneanother through an Inter-RAT eXchange Function (IRXF) Module 356.

In various embodiments, the network node (e.g. 224) acting as a servercomprises a first communication link corresponding to data to/from thefirst RAT and a second communication link corresponding to data to/fromthe second RAT.

Turning now to FIG. 4, a schematic representation is shown. Theschematic may be indicative of a front-end associated with a device,such as the antenna and front end 306 of FIG. 3.

A chassis 402 is shown in FIG. 4. The chassis 402 may be modeled orinclude one or more of a capacitor Cc, an inductor Lc, and a resistorRc. Furthermore, one or both of the capacitor Cc and the inductor Lc maybe varied or tuned, which may provide for a variable reactance withrespect to the chassis 402.

The chassis 402 may be associated with, or include, a ground plane thatmay serve as a reference point with respect to an antenna 404. Theantenna 404 may be modeled or include one or both of a resistor Ra and areactance Xa. The reactance Xa may be implemented as a (variable ortunable) capacitor and/or an inductor.

The chassis 402 and antenna 404 may be modeled as being combined orelectrically coupled to one another via a coupling factor N. In someembodiments, a radiation performance of the antenna 404 may be improvedvia the model shown in FIG. 4, such that the coupling factor Nincreases. The radiation performance may be measured in accordance withone or more parameters or criteria, such as bandwidth and efficiency.The antenna-chassis combination may form the overall radiationperformance of the antenna 404, particularly at operating frequenciesbelow 1 GHz.

In some embodiments, the radiation performance may be improved orenhanced by tuning one or more components associated with the chassis402. For example, a resonance of a ground plane associated with thechassis 402 may be made to match the antenna 404, thereby satisfying therelation: f.sub.antenna=f.sub.chassis that improves the overall antennaradiation performance.

FIG. 5 illustrates an example of the chassis 402. The chassis may bemade of one or more materials. For example, the chassis 402 may includea dielectric material and conductive material layer, e.g., a metal layeron the dielectric material. In an example, the metal is a copper layer.The chassis 402 may be manufactured as a printed circuit board (PCB).The chassis 402 may be fabricated with a feed line 504. The feed line504 may be used to connect the antenna 404 to a transmitter or receiver.Various components (e.g., electrical components and/or mechanicalcomponents) known to those of skill in the art may be used to couple thechassis 402 and the antenna 404.

FIG. 6A illustrates an embodiment showing a modification of the chassis402 of FIG. 5 to include one or more components. For example, FIG. 6Ashows the inclusion of a varactor 602 and an inductor 604. In someembodiments, one or more decoupling capacitors 606 may be included toimprove performance (e.g., to filter noise) and facilitate the biasingof the tunable capacitor/varactor 602.

The components shown in FIG. 6A may be associated with a slot 608. Theslot 608 may be formed by etching conductive material, e.g., a metallayer, associated with the chassis 402 to expose the dielectricmaterial. In other examples, the conductive material is formed on thedielectric layer by a positive process where the conductive material islaid down outside the slot 608. The location of the slot is such that toattract the surface currents on the chassis, usually placed in alignmentto one or more of the chassis edges. One or more of the components maythen be placed on the dielectric and in contact with metal of the etchedslot 608.

FIG. 6B illustrates another modification of the chassis 402 of FIG. 5 toinclude one or more components. For example, FIG. 6B shows the inclusionof inductors 652 and 654 in association with a slot 656.

FIG. 7 illustrates a flow chart of a method that may be used toconstruct or fabricate a tunable chassis, such as a chassis 402 inconnection with one or more of FIGS. 4, 5, 6A and/or 6B. The chassis maybe fabricated to control radiation associated with an antenna (e.g.,antenna 404). In some embodiments, the chassis is tuned to improve theresonance relation with that of the antenna. The tuning can also be usedto tune the chassis-antenna resonance at multiple frequencies.

In block 702, currents (e.g., surface currents) in an area of thechassis may be identified to select a location to electrically connectthe antenna and the chassis. The area or location of the currents may beidentified using one or more techniques, such as trial-and-error,simulation, or any other technique available to a skilled artisan.

In block 704, a slot may be formed in the chassis. The slot may beformed by etching a portion of the chassis as described above. The slotmay include an open end in some embodiments.

In block 706, the formed slot may be aligned with a longitudinal edge ofthe chassis. Such alignment may be used to provide for a high degree ofcoupling (N) between the antenna and the chassis. The slot may extend toalign with a shorter edge of the chassis in some embodiments.

In block 708, the slot may be loaded with one or more tunable components(e.g., a tunable or variable capacitor). In some embodiments, one ormore components (e.g., tunable components) may be switched in or out inorder to modify a radiation performance associated with the antenna.Different performance characteristics may be obtained by changing alocation of one or more components.

In block 710, one or more components may be varied or tuned. The tuningmay be conducted to obtain a selected radiation performance profile forthe antenna.

As described above, in some embodiments an antenna structure might notbe altered to obtain a tunable antenna. In other words, the antenna maybe designed in accordance with a fixed configuration and then turnedinto a tunable antenna through a ground plane electric coupling.Placement options may be more flexible when using the on-ground tuningapproach relative to actually tuning the antenna. Using such anapproach, effects of traces used for biasing capacitors may be reducedor minimized while also providing for a more stable placement of activeelements on the ground plane. A broad bandwidth may be obtained, asreturn loss might not suffer with the bandwidth since the electricalcoupling between the antenna and the ground plane may be optimized witheach frequency tuning while maintaining the antenna bandwidth.

A structure of an antenna (e.g., antenna 404) may be modified in someembodiments in order to realize a tunable antenna. An example of such amodified antenna structure is shown in FIG. 8 where tuning is achievedcontrolling the surface currents at the antenna radiating structure. InFIG. 8, an antenna 802 (which may correspond to antenna 404) generallymay assume a sawed or a meandered arm shape. The antenna 802 may beapproximately 29 millimeters (mm) long and 7 mm high. The antenna 802may be loaded with a (variable) capacitor 804 connected in series withan inductor 806. The antenna 802 may have a meandering or foldingprofile or configuration, such that an effective length or size of theantenna 802 may be realized without increasing the physical length orsize of the antenna 802, where the effective length/size corresponds tothe electrical length/size of the antenna 802, and the physicallength/size of the antenna may correspond to a measurement of theantenna 802 from a first end 802-1 to a second end 802-2. The antenna802 may be designed to cover a particular band or range of frequencies,such as 680 MHz to 980 MHz, for example. Coupling to a ground plane maybe achieved through the alignment of the lower part (e.g., the elongatedarm) of the antenna structure 802 with the longitudinal edge of thechassis.

FIG. 9 illustrates a modified antenna structure 902. The antenna 902 maybe similar to the antenna 802 of FIG. 8, except the antenna 902 may beslightly longer (e.g., 2-5 millimeters longer, 32 mm compared to 29 mmfor antenna 802). The longer actual length for antenna 902 may come fromless meandering relative to the antenna 802. The spaces within theantenna 902 may be used to place, e.g., buttons or keys, which may beuseful in connection with a computing device (e.g., a mobile or handhelddevice). For example, such buttons or keys may be used to providefunctionality (e.g., an input/output interface) with respect to thecomputing device.

FIG. 10 illustrates a modified antenna structure 1002. The antenna 1002may correspond to an effective combination of the antennas 802 and 902in an interleaving manner and may be used to achieve independent highand low band on antenna tuning through two meandered and folded arms.The antenna 1002 may be 29 mm long and 7 mm in height. The antenna 1002may include a first set of components, such as a tunable capacitor 1004connected in series with an inductor 1006, to obtain a tuning over afirst frequency band (e.g., the low band). The antenna 1002 may includea second set of components, such as a tunable capacitor 1008 connectedin series with an inductor 1010, to obtain a tuning over a secondfrequency band (e.g., the high band). The tuning components may belocated on, e.g., inverted-F antenna (IFA) arms just after a feedlocation in order to maximize a tuning range. In some embodiments, theantenna utilizes coupling with the ground plane electrically through thelongitudinal edges of the chassis, and thus, does not require groundclearance and features a compact physical size.

FIG. 11 illustrates a modified antenna structure 1102. In FIG. 11,ground coupling may be used to improve or enhance performance byincluding a coupling arm 1108, thereby allowing a reduction in thelength of the antenna 1102. In addition to the coupling arm 1108, theantenna 1102 may include an upper arm 1112. The antenna 1102 may be 32mm long and 7 mm high. Tuning may be achieved via a capacitor 1110 andinductor 1106 arranged in a parallel fashion with respect to oneanother, thereby providing an additional resonance for, e.g., high andlow band tuning Additional components, such as a capacitor 1104, may beincluded. In some embodiments, the capacitor 1104 may be used as adecoupling capacitor and may facilitate biasing one or more components,such as a varacator or the capacitor 1110.

In some embodiments, the location of an antenna (e.g., one or more ofantennas 802, 902, 1002, and 1102) may be based on a location of one ormore slots on a chassis (e.g. slots 608 and 656). For example, thelocation of the antenna may be selected based on a shape, configuration,or geometry associated with the antenna. The location of the antenna maybe selected so as to control or configure currents associated with aground plane of the chassis. In some embodiments, the electrical lengthof a slot may be tuned through loadings of the slot to improveperformance or change a frequency of operation.

FIG. 12A illustrates a flow chart of a method that may be used toconstruct or fabricate an antenna, such as one or more of the antennasshown in connection with FIGS. 8-11. The antenna may be fabricated toprovide control over radiation associated with the antenna.

In block 1202, a location may be selected on a radiating structure ofthe antenna. The location may be selected based on an identification ofa maximum surface current at a frequency or frequency range/band ofinterest. The location may be identified using one or more techniques,such as those described above.

In block 1204, at least one tunable component may be loaded at thelocation selected in block 1202.

In block 1206, the antenna may be electrically coupled to a chassis. Thecoupling may occur by aligning an elongated part of the structure with alongitudinal edge of the chassis. In some embodiments, the antenna mightnot include any clearance with respect to a ground or ground planeassociated with the chassis.

In block 1208, one or more components may be tuned. For example, atunable component loaded in connection with block 1204 may be tuned inblock 1208.

FIG. 12B illustrates a flow chart of a method that may be used to tune aground plane or chassis (e.g., chassis 402 of FIG. 4). The tuning may beperformed after the chassis and/or an antenna is fabricated. The tuningmay be performed to, e.g., match carrier requirements during use, toimprove performance during use, etc.

In block 1252, one or more components located on, e.g., the chassis maybe tuned. The tuning may occur in real-time. In some embodiments, a(pre-defined) table of values may be used to select or set a value forone or more of the components. The values may be based at least in parton an operating frequency or frequency range(s)/band(s) of interest. Thevalues used for the components may be tuned to optimize or maximizeradiation performance at the operating frequency or frequencyrange(s)/band(s). The table may include settings to improve performance,to compensate for detuning effects potentially brought about by, e.g., auser, etc.

In block 1254, one or more signals may be measured. The signals may beassociated with a transmission or a reception with respect to, e.g., ahandset. In some embodiments, the signals may include one or more testsignals.

In block 1256, the signals measured in block 1254 may be compared to oneor more thresholds. The thresholds may be selected so as to ensure aparticular level of performance.

In block 1258, a determination may be made whether the measuredsignal(s) exceed the threshold(s) based on the comparison of block 1256.If the measured signal(s) exceed the threshold(s) (e.g., the “Yes” pathis taken out of block 1258), then flow may proceed from block 1258 toblock 1252 to tune one or more of the components. On the other hand, ifthe measured signal(s) do not exceed the threshold(s) (e.g., the “No”path is taken out of block 1258), then flow may proceed from block 1258to block 1254 to continue measuring the signal(s). Execution of themethod of FIG. 12B may be used to monitor performance (e.g., radiationperformance) associated with an antenna, and based on the monitoredperformance, an adjustment or tuning may occur.

FIG. 13A illustrates a line drawing of an exemplary chassis 1302 coupledto an antenna 1304 in accordance with one or more embodiments. As shown,the chassis 1302 may be approximately 95 millimeters (mm) in length and60 mm in width. The antenna 1304 may be approximately 9 mm in height andthe antenna may be coupled to a dielectric material 1306 that isapproximately 60 mm in length.

FIG. 13B illustrates a zoomed-in view of the antenna 1304 of FIG. 13A.As shown in FIG. 13B, the antenna 1304 may take the form of a foldedsawed arm. In some embodiments, dimensions shown in FIG. 13B may be asfollows: W=2 mm, W.sub.1=2.5 mm, W.sub.2=7 mm, d.sub.s=0.5 mm, W.sub.f=1mm, and L.sub.t=29 mm.

The line drawings of FIGS. 13A and 13B may correspond to the embodimentshown in FIG. 8. While not explicitly shown in FIGS. 13A and 13B, thechassis 1302 and/or the antenna 1304 may include a slot and one or moretunable components, such as the capacitor 804 and the inductor 806. Thechassis 1302 may be associated with a ground plane.

FIG. 14 illustrates a line drawing of an exemplary antenna 1404 inaccordance with one or more embodiments. As shown in FIG. 14, theantenna 1404 may take the form of a flipped folded sawed arm. In someembodiments, dimensions shown in FIG. 14 may be as follows: W=2 mm,W.sub.1=2.5 mm, W.sub.2=7 mm, d.sub.s=0.5 mm, W.sub.f=1 mm, d.sub.saw=2mm, and L.sub.t=29 mm.

The line drawing of FIG. 14 may correspond to the embodiment shown inFIG. 9. While not explicitly shown in FIG. 14, the antenna 1404 mayinclude one or more tunable components, such as the capacitor 804 andthe inductor 806. The antenna 1404 may be coupled to a chassis 1402 thatmay: (1) be associated with a ground plane, and (2) include a slot.

FIG. 15 illustrates a line drawing of an exemplary antenna 1504 inaccordance with one or more embodiments. As shown in FIG. 15, theantenna 1504 may take the form of an inverted-F antenna (IFA) with acoupling arm. In some embodiments, dimensions shown in FIG. 15 may be asfollows: W=2 mm, W.sub.1=2.5 mm, W.sub.2=7 mm, d.sub.s=0.5 mm, andL.sub.t=29 mm.

The line drawing of FIG. 15 may correspond to the embodiment shown inFIG. 11. While not explicitly shown in FIG. 15, the antenna 1504 mayinclude one or more tunable components, such as the capacitor 1110 andthe inductor 1106. The antenna 1504 may be coupled to a chassis 1502that may: (1) be associated with a ground plane, and (2) include a slot.

FIG. 16 illustrates a line drawing of an exemplary antenna 1604 inaccordance with one or more embodiments. As shown in FIG. 16, theantenna 1604 may be associated with a layout to support multi-bandoperation. For example, a capacitor C900 and an inductor L900 may beassociated with a first band (e.g., frequency band) of operation, and acapacitor C1800 and an inductor L1800 may be associated with a secondband of operation.

The line drawing of FIG. 16 may correspond to the embodiment shown inFIG. 10. The capacitor C900 and the inductor L900 may correspond tocapacitor 1004 and inductor 1006, respectively. The capacitor C1800 andthe inductor L1800 may correspond to the capacitor 1008 and the inductor1010, respectively. The antenna 1604 may be coupled to a chassis 1602that may: (1) be associated with a ground plane, and (2) include a slot.

The various dimensions described above and shown in connection with theFigures (e.g., FIGS. 13A, 13B, and 14-16) are illustrative. Other sizesor values for the dimensions may be used in some embodiments. In someembodiments, values for dimensions or parameters shown in the Figuresmay be determined via analysis and/or simulation (e.g., computersimulation).

In some embodiments, an effective tuning of an antenna may be performedin real-time. For example, a tuning of components located on a chassis(e.g., chassis 402) may be done in real-time on a handset. A(pre-defined) table of values may be used to select or set a value forone or more of the components. The values may be based at least in parton an operating frequency or frequency range(s)/band(s) of interest. Thevalues used for the components may be tuned to optimize or maximizeradiation performance at the operating frequency or frequencyrange(s)/band(s). The table may include settings to improve performance,to compensate for detuning effects potentially brought about by, e.g., auser, etc.

As described herein, aspects of the disclosure may be used to design,fabricate, and use an antenna. The antenna may be associated with acomputing device. The antenna may be tuned in connection with one ormore frequencies or frequency bands/ranges. In some embodiments, anelement may be tuned. For example, a tunable element may include a slotor an antenna.

As described herein, in some embodiments various functions or acts maytake place at a given location and/or in connection with the operationof one or more apparatuses, systems, or devices. For example, in someembodiments, a portion of a given function or act may be performed at afirst device or location, and the remainder of the function or act maybe performed at one or more additional devices or locations.

Embodiments of the disclosure may be implemented using one or moretechnologies. In some embodiments, an apparatus or system may includeone or more processors, and memory storing instructions that, whenexecuted by the one or more processors, cause the apparatus or system toperform one or more methodological acts as described herein. Variousmechanical components known to those of skill in the art may be used insome embodiments.

Embodiments of the disclosure may be implemented as one or moreapparatuses, systems, and/or methods. In some embodiments, instructionsmay be stored on one or more computer-readable media, such as atransitory and/or non-transitory computer-readable medium. Theinstructions, when executed, may cause an entity (e.g., an apparatus orsystem) to perform one or more methodological acts as described herein.In some embodiments, the functionality described herein may beimplemented in hardware, software, firmware, or any combination thereof.

Embodiments of the disclosure may be tied to one or more particularmachines. For example, one or more tunable components may be loaded on achassis. One or more tunable components may be loaded on an antennastructure. The location of the tunable components may be identifiedbased on a simulation performed on a computing device.

The particular embodiments disclosed above are illustrative only andshould not be taken as limitations upon the present disclosure, as thedisclosure may be modified and practiced in different but equivalentmanners apparent to those skilled in the art having the benefit of theteachings herein. Accordingly, the foregoing description is not intendedto limit the disclosure to the particular form set forth, but on thecontrary, is intended to cover such alternatives, modifications andequivalents as may be included within the spirit and scope of thedisclosure as defined by the appended claims so that those skilled inthe art should understand that they can make various changes,substitutions and alterations without departing from the spirit andscope of the disclosure in its broadest form.

What is claimed is:
 1. A wireless communication device comprising: anantenna; a chassis electrically coupled to the antenna, wherein thechassis comprises a conductive portion, wherein a slot is formed throughthe conductive portion; a tuning circuit connected with the antenna, thetuning circuit positioned in proximity to an edge of the chassis, thetuning circuit comprising a group of inductors, a capacitor and aswitch, wherein the switch is operably connected with the group ofinductors, and wherein the capacitor is operably connected in serieswith an inductor of the group of inductors; and a controller connectedwith the switch, wherein the controller causes the switch to selectivelyelectrically connect or disconnect at least one of the group ofinductors to adjust a radiation performance associated with the antenna.2. The wireless communication device of claim 1, wherein the chassiscomprises a dielectric layer, wherein the group of inductors ispositioned along the slot.
 3. The wireless communication device of claim2, wherein the slot is in proximity to and parallel with an edge of thechassis.
 4. The wireless communication device of claim 2, wherein thechassis has a pair of long edges and a pair of short edges, and whereinthe slot is in proximity to and parallel with one of the short edges. 5.The wireless communication device of claim 4, wherein the slot extendsfrom at least one of the long edges.
 6. The wireless communicationdevice of claim 1, wherein different inductors of the group of inductorsare utilized for different frequency bands of operation.
 7. The wirelesscommunication device of claim 1, wherein the capacitor is a singlecapacitor.
 8. The wireless communication device of claim 7, wherein thesingle capacitor is connected in series with a single inductor of thegroup of inductors.
 9. The wireless communication device of claim 7,further comprising a memory, wherein the selectively electricallyconnecting or disconnecting the at least one of the group of inductorsto adjust the radiation performance is based on data stored in a look-uptable in the memory.
 10. The wireless communication device of claim 7,wherein the selectively electrically connecting or disconnecting the atleast one of the group of inductors to adjust the radiation performanceis based on measurements obtained during operations of the wirelesscommunication device.
 11. A method comprising: determining, by aprocessor of a wireless communication device, a target radiationperformance associated with an antenna of the wireless communicationdevice; identifying, by the processor, a target tuning state for atuning circuit according to the target radiation performance, the tuningcircuit being connected with the antenna; adjusting, by the processor, aswitch to configure the tuning circuit into the target tuning state,wherein the tuning circuit comprises a group of inductors positioned inproximity to a short edge of a chassis of the wireless communicationdevice, wherein the switch is operably connected with the group ofinductors, and wherein the adjusting of the switch selectivelyelectrically connects or disconnects the at least one of the group ofinductors to adjust the radiation performance associated with theantenna.
 12. The method of claim 11, further comprising measuring anoperational parameter during operations of the wireless communicationdevice, wherein the adjusting of the switch to configure the tuningcircuit into the target tuning state is based on the operationalparameter.
 13. The method of claim 11, wherein the identifying of thetarget tuning state for the tuning circuit according to the targetradiation performance is based on data stored in a look-up table in amemory of the wireless communication device.
 14. The method of claim 13,wherein the data comprises thresholds for a group of measuredparameters.
 15. The method of claim 11, wherein the tuning circuitcomprises a single capacitor operably connected in series with a singleinductor of the group of inductors.
 16. The method of claim 11, whereindifferent inductors of the group of inductors are selected for switchingfor different frequency bands of operation of the wireless communicationdevice.
 17. The method of claim 11, wherein the chassis comprises aconductive layer and a dielectric layer, wherein a slot is formedthrough the conductive layer, wherein the group of inductors ispositioned along the slot, wherein the slot is in proximity to andparallel with the short edge of the chassis, and wherein the slotextends from a long edge of the chassis.
 18. A wireless communicationdevice comprising: an antenna; a chassis electrically coupled to theantenna, the chassis having a long edge and a short edge; a tuningcircuit connected with the antenna, the tuning circuit positioned inproximity to a short edge of the chassis, the tuning circuit comprisinga group of reactive elements and a switch, wherein the switch isoperably connected with the group of reactive elements; and a controllerconnected with the switch, wherein the controller causes the switch toselectively electrically connect or disconnect at least one of the groupof reactive elements to adjust a radiation performance associated withthe antenna.
 19. The wireless communication device of claim 18, whereinthe tuning circuit comprises a capacitor that is connected with a singleinductor of the group of reactive elements.
 20. The wirelesscommunication device of claim 18, wherein the chassis includes a slot inproximity to the short edge of the chassis, wherein the chassis has apair of long edges, and wherein the slot is in proximity to one of thelong edges, and further comprising a memory, wherein the selectivelyelectrically connecting or disconnecting of the at least one of thegroup of reactive elements to adjust the radiation performance comprisesidentifying a target tuning state for the tuning circuit according todata stored in a look-up table in the memory, wherein the data comprisesthresholds for a group of measured parameters associated with operationsof the wireless communication device.